This disclosure generally relates to a process for the combinatorial production of material compositions from a single sample, and more particularly, to a process which employs the use of diffusion multiples to create large numbers of compositions in the single sample.
Structural materials such as superalloys and steels provide the mechanical properties for building jet engines, power generation turbines, cars, and the like. Significant time and effort is typically required to discover and optimize new compounds. One of the problems affecting the rate of development is that it is oftentimes very difficult to predict the physical and chemical properties of various compounds or material combinations, particularly for compounds or material combinations that have been produced using different processing conditions. Traditionally, most of these properties and/or behaviors are evaluated one at a time from individual alloys or by the use of binary systems, i.e., diffusion couples. A diffusion couple generally comprises two dissimilar materials, e.g., metals, metal alloys, ceramics, and the like, that are placed in good thermodynamic contact with one another. The materials are then heated at an elevated temperature for a defined period of time. An alloy interdiffusion region will exist in location of the couple, where atoms have diffused into one another. Diffusion couples, which can provide greater amounts of data than analysis of individual alloys, have been used to determine phase diagrams and evaluate diffusion coefficients.
Extending the concept from the binary systems into multi-component systems, a diffusion multiple has been employed to generate libraries of multi-component compositions for combinatorial surveys of critical materials. Generally, a diffusion multiple is an assembly of three to four different metal (or ceramic) blocks, in intimate interfacial contact, and subjected to a high temperature to allow thermal interdiffusion. The diffusion multiple is typically fabricated by inserting quarter pie shapes of metals or metal oxides into a cylindrical sleeve of a pure metal. The cylindrical sleeve is then capped at both ends with the pure metal and the entire assembly is heated at an elevated temperature for a defined period of time to promote interdiffusion at the various interfaces defined by the quarter-pie shapes. As such, the data available by the diffusion multiple arrangement and geometry as described above, while a significant advance over one-at-a-time analysis and the use of binary systems, still tends to be limited.
Accordingly, there remains a need for more versatile diffusion multiple arrangements and geometries for providing even greater amounts of data.